本研究是使用水平式三區真空爐管，以熱氧化法製備氧化銅奈米線，藉由觀察溫度、持溫時間、升溫速率，以及氧氣分壓等四個參數的形貌變化，可以推論出一個應力釋放的生長機制，奈米線的生長取決於熱應力累積的速率。我們也針對CuO奈米線進行性質的改良，以純硫粉進行二次退火的實驗，成功合成出CuO-CuS核殼奈米線結構。研究中以SEM、XRD做初步的鑑定，並透過TEM的高解析影像以及STEM mode的line scanning確認其核殼奈米線結構，最後針對CuO-CuS核殼奈米線以及CuO奈米線進行簡易的光催化降解實驗以及電性量測，以LED燈照光4小時後，CuO-CuS核殼奈米線的亞甲基藍降解率為89%較CuO奈米線的67%提升了22%，說明此結構對於光催化是有幫助的，有潛力應用於可見光光降解。

In this study, a simple and inexpensive way to synthesize CuO-CuS core-shell nanowires by two-step annealing process was reported. CuO nanowires were prepared on copper foil via thermal oxidation in a three-zone horizontal tube furnace. In order to get larger surface area, we adjusted four processing parameters to improve the aspect ratio and number density of CuO nanowires. A second-step annealing process was conducted to synthesize CuO-CuS core-shell nanowires by sulfur powder under low pressure. SEM and XRD were used to investigate the morphology and crystal structure of nanowires. TEM analysis, including HR-TEM, SAED, EDS, STEM line scanning, was used to identify the core-shell structure of nanowire, and confirm the composition of core and shell respectively. The photocatalytic properties were evaluated by the degradation of methylene blue (MB) under visible light irradiation. Compare CuO-CuS core-shell nanowires with CuO nanowires, the 4-hour degradation rate are 89% and 67%, respectively. The results demonstrated CuO-CuS core-shell nanowires have a promising application in photocatalyst.

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